Four people were killed and two wounded after sundown Tuesday when a missile fired from by the IDF navy hit a car outside a Hamas security headquarters building in Gaza City, Palestinian hospital and security officials said.
The blast went off on the Gaza beachfront near the Hamas marine police force offices.
The IDF had no comment.
Israel has been carrying out airstrikes in Gaza aimed at terrorists who plan or carry out rocket attacks on southern Israel.
Also, Gaza has been hit by factional fighting between Hamas and Fatah. In June, Hamas overran the seaside territory, vanquishing the Fatah-linked security forces.